It's something similar to this:€ 16,99 32%OFF | Universal Adjustable Fuel Pressure Regulator Oil 100psi Gauge AN 6 Fitting End-Black a.aliexpress.com/_mOKodL7 Just een universal fuel pressure regulator. Don't crack it up to much. Just 0.1 or 0.2 is enough.

@@joosie54321 Thanks for the reply! I'm thinking of switching to a set of 4 hole Bosch EV14 injectors for better fuel atomization and wanted the ability to adjust fuel pressure to keep the correct a/f ratio with the new injectors. On paper it seems I will need about 2.8 bar to compensate. Did you keep the vacuum line from cyl #4 connected to the new regulator?

@@Chrii656 That's a nice mod. Yeah kept it connected. Worked well.

Hello DSV, Sadly I can't help you with the specs of the bike. Most of the stuff was build by the guys themselves. The lower engine casing was zundapp. But al the internals are modified. Costom made balanced crankshaft, special clutch housing. 6 speed instead of the regular 5. If you're not bound to zundapp, beter go for a mordern Derbi AM6 engine. Take care.

@@joosie54321 Ik heb nu AM6. Er is een kleine cilinder, een carburateur voor 24 minuten, maar hij geeft 12 shp uit. Ik wilde weten welke cilinder je had, of vertel me met wie ik contact moest opnemen, goed geluid van je motor, goed gedaan!

Look voor ZUNDAPP RVRT video's. You'll need to have contact with them. I have myself a 80cc polini kit on my zundapp. Longer stroke crankshaft. 28mm carb. MVT premium ignition. Custom exhaust.

Klopt, 5bak. Heb er uiteindelijk nog veren van een 125 in moeten zetten. Die verhelpen het.

@@joosie54321 heb je hem nog? En polini 75 getüned door Rob van Rossum?

In Holland en Germany you can buy a lot of parts for zundapps. I think also some stuff for KS175. Sites likes: Jmpbparts.com Zundapp.nl And a lot on ebay I think

@@joosie54321 thanks a lot

Hangt een ronde 5 bak onder

Bram Van Der Meer Hij is al eens op de bank geweest. Hoogste wat ik ermee gehaald heb is 19.1 PK

David Fiege Doen ze gewoon met een zundapp 50cc onderblok. Verder wel helemaal aangepast. Dacht tegenwoordig zelfs een zesbak. Krukas enz enz enz. Huis getunede cilinder. 50cc. Al over de 20pk heen

xr134, Dit heb ik gewoon bij een motoport gedaan. Dit was voor de verzekering genoeg. Alleen de politie was minder tevreden. Ze zagen het alsnog als rijden zonder geldig rbw. Beschik inmiddels over m'n A rbw.

erg jammer! had graag zonder problemen op een k100 gereden met A2

Behind the throttle bodies is the stock place for you're fuel pressure regulator. I don't see the problem of that spot. The fuel that you inject is not going along this way. The fuel you inject goes straight from tank to fuelrail into the injectors. The line that's running behind the TB's is for the extra fuel, to reduce the pressure. Fuel pump gives like 6bar or something. And you use actually 2.1bar at the injectors. If the stock fuel regulator is broken, you should fix. Otherwise leave it. If you want higher pressure, you can buy a adjustable one. And then you can go To 2.6bar, you'll notice the difference. 3bar is to much, runs not that great.

Joost, What it looks like to me is that fuel goes from the forward of the two outlets of the fuel tank, to the fuel pressure regulator, which sits on the top of the block right behind the radiator, which is the hot spot because the line is long, goes right along the top of the block behind the radiator, to the regulator, and then to the forward inlet of the fuel rail. With this stock set up, the fuel gets every opportunity to heat up, and this is giving me the vapor lock. When I get vapor lock, it dies, and along side of the road, I remove the gas cap assembly, and look at the fuel pump, and with the key off, nothing running, I get a steady stream of tiny bubbles coming up from the bottom of the fuel pump. So what it looks like to me is that the bubbles are backing up, going up into the top of the fuel pump, and out the bottom. When the fuel pump has all these vapor bubbles, it can't pump . (When the gas cools off, and the steady stream of bubbles stops, it will run again). It just spins in the vapor or something. So I would like to mount a new fuel pump (an adjustable one, as you suggest) and mount it in some cooler place, keeping it and the long line away from the top of the motor and away from behind the radiator. Mine always seemed to have just a bit of a flat spot right off of idle, so I'm thinking that just a bit more fuel pressure might help that. I just replaced the y pipe and breather hose, and I think I have all the air leaks stopped. It actually runs quite well now, but there seems to be a bit of a flat spot right off of idle. So what kind of adjustable one should I be looking for? Any part numbers? I don't know anything about these regulators. Yours sounds awesome right off of idle.

Ray Brensike Have you ever had the fuel lines of to check the flow? If you look at internet, search for "fuel pressure regulator diagram" you'll see at some pictures that a K100 has a return system. It will "bleeds off" the extra fuel back to the tank. If you're interested in the regulator. This is the one I use. shop.wiltec.info/product_info.php?info=p2604_Race-Tech-R-variabler-Benzindruckregler-0-10bar-stufenlos-einstellbar.html&tpl=mobile Hope you can fix the problems ;)

Joost, Thanks for the info. While I was looking for what I could on fuel pressure regulators, I ran across an article on "Symptoms Of A Fuel Pressure Regulator", and one of the things it said was, "black soot coming out of the tail pipe is a sure symptom of a bad fuel pressure regulator", and This I have had on my old van for about ten years, and every time I fail emissions I take it to a mechanic and he says, "Well something is wrong with it, and I don't know what it is." and I say, "OK Thanks, here is $150.00. Anyway I've lost some gas mileage on the Beemer and as long as I was going to move the location of the fuel pressure regulator anyway, I was wondering if it's going a bit bad and if that might account for some lost gas mileage. It does have some black soot inside the tail pipe. Maybe I will get an adjustable one.

Does that link still work?

Surya Perkasa Im not sure. It's a long time ago. Hpi or Ignitech.

Joost M whoa nice bike!!! Thanks for reply...

For who? For himself? Why would you care about his eventual injuries?

+Daan B Dat zie je goed. De begrenzer zit in het gashendel. Hij is alleen op vermogen afgesteld. De demper moet ik nog maken, die zal niet tot nauwelijks verschil maken in pk's. Zou ik eerder vanaf begin moeten beginnen en gaan spelen met diameters.